When this article about “sergercore” came up in my newsfeed, I had a good chuckle.

What a ridiculous word, right? It’s right up there with “normcore.”

I won’t keep you hanging on the definition of sergercore. It’s garments with exposed serger (overlocker) stitching. Yeah, seams on the outside of garments. Visible serger work.

Some sergercore is patched pieces of fabric (usually knit, from what I can tell). Some of it is lines of stitching on one piece of fabric (the fabric is folded and overlocked or the stitching is on the edge of the fabric).

The neck is finished with french binding for a knit neckline with a twist — I did it backward/inside out so the raw edge is on the outside. I thought it would look cool with the exposed serger stitching.

According to the article, sergercore is surging on online fast-fashion site Shein and with some boutique fashion designers (who charge in the hundreds of dollars — ya gotta check out the article).

So. I have a serger. I sew clothes. I can try sergercore — and share the outcome with my sewing besties (that’s YOU)!

This article starts with T-shirt details (cos I know you want to know about the fabric and pattern), and the final bit features my tips for taking on a sergercore project.

This post features affiliate links chosen for you. If you click through and make a purchase, I may receive a commission at no additional cost to you. Affiliate advertising is the main way I earn income from Sie Macht, and I thank you for your support!

Sergercore T Fabric Details

This is a lightweight linen knit that I got from Mood Fabrics in New York. I had some time in the city before Camp Workroom Social, so you KNOW I made a pilgrimage to the Holiest of Fabric Holies.

It has a wonderfully nubbly texture that’s neither soft nor scratchy. You definitely can tell it’s linen; it’s cool to “see” the fiber behind the fabric. And, because it’s linen, it’s keeps this gal feeling cool in terms of body temp.

At first I wasn’t sure about doing this fabric as a single layer, as it is very light. I thought, actually, that I might do two front bodice layers and put the serger stitching on the bottom layer.


RELATED: Beginner Serger Supplies: What You Need for a New Serger


For me, the transparency test was seeing how a nude-colored bra looked underneath as I draped the linen knit over it. Yeah, you can *kinda* see a nude bra (worn in these pics) through the shirt, but sometimes ya just gotta live you life and say, “Well, I guess if other people can see it, at least they know I’m WEARING a bra.”

Anyhoo, I didn’t double up on the fabric, and it’s a good thing, because I had juuuust enough yardage for a single T-shirt. I had to cut the back pattern piece as two pieces vs. on the fold.


RELATED: Best Serger Hems for Thin Knit Fabrics


Sergercore T-Shirt Sewing Pattern

This is a Sie Macht Cass T-shirt, size 6/8B. This pattern is a great canvas for sergercore, because it’s a basic top with more surface area than your regular T-shirt. More surface area = more room for serger stuffs.

In my biased opinion, the shoulder seams, which fall on the FRONT of the shoulders, are particularly good candidates for visible seaming.

ALSO: If you are sensitive to seams on the inside of your clothes, trying a sergercore lewk on Cass is right up your alley. The relaxed-fit T-shirt doesn’t cling to your skin, and even if it did, the rough seams are on the outside!

Cass T-shirt call to action

You’re invited to download the Cass T-shirt PDF. It comes in misses and plus size ranges, and it’s only three pattern pieces, so it stitches up F-A-S-T. Basically the perfect shirt for sergercore and other sewing pattern experimentation. If you sew your own Cass, please tag me — @sie.macht.sewing, #smcass.

P.S. If you’d like some other choice articles about sewing Cass (or any other T-shirt), check out these articles:

Tips for DIY Sergercore

OK, back to all-things sergercore! Here are my notes, compiled while sewing my own sergercore T.

1.) Use Different Kinds of Thread

In this simple T-shirt, I used:

  • 4-thread overlock (for shoulder and side seams and hem and sleeve edges)
  • 3-thread flatlock seaming (stitched stripes)
  • 2-thread flatlock (stitched stripes)

The most visible thread used is a fluffy white nylon, which was in the upper looper position no matter which stitch I used. The other threads (needle and lower looper) were regular polyester serger threads.

In a wide stitch, I knew the upper looper thread was going to have the starring role, swooping back and forth in a fat zig-zag. The puffy nylon thread adds great dimensionality to the already-pronounced serger stitches. And I love love love how it looks against the linen texture.

Now, if you wanted something shiny, you could use rayon thread. Or you could experiment with beefy embroidery thread (consult your serger manual for how to thread specialty threads, natch).

Don’t think you’re married to cones of poly serger thread. Test some weirdo options and surprise yourself. For even more ideas, check out serger whisperer Gail Yellen on YouTube.

Serging for decoration. Get into it.


RELATED: Easy French Binding for Knit Necklines (How To)


2.) Ask: Texture or Contrast?

My stitches were made with a combo of white and off-white threads. I was more interested in adding texture, something to vibe with the texture of the linen.

For a completely different look, I could have used contrasting thread — maybe a DARK blue, yellow/orange (complementary colors), or green or purple (analogous colors). Or anything else I/you could think of.

Thread that blends in is going to add texture; thread that stands out is going to add contrast. No correct choice, only preference.

3.) Ask: Precise or Organic?

To create this garment, I first serged “stripes” across my total yardage (selvage to selvage). Then I cut out my pattern pieces. In a way, I kinda sorta created a new textile for the T-shirt (that’s a VERY generous definition of creation, obvs).

I wanted imperfect, organic lines of stitching, so I didn’t worry about even spacing between stripes or keeping them level across the yard of linen knit. After each line of stitching, I took the fabric from the serger, laid it out on my sewing room desk, evaluated what I had done, and loosely planned the next line of serging.

If you’d like precise lines (vs. organic ones), I suggest using a fabric marking tool to establish EXACTLY where you need to serge.

OH YES — should it tickle your fancy, you absolutely should try vertical and bias lines of serging. I only wanted (mostly) horizontal lines, so that’s why there are no vertical stripes (save for the center-back seam).

4.) Get Your Fabric Back into Shape

Once I finished my lines of serging, I noticed that my fabric was a bit stretched out of shape. This was no surprise, as I was creating loooong serged stripes on a stretchy fabric.

Obviously when you’re serging, try your best not to stretch the fabric. But if your yardage ends up a little wonky from use/abuse, toss it in the clothes dryer with a wet hand towel.

The linen knit and a wet (not dripping but more than damp) hand towel tumbled in my dryer for 60 minutes on high. This treatment won’t shrink your yardage, but it will help it snap back into shape.

And, when it’s snapped back into shape, that’s when you can cut out the pattern pieces.

5.) Adding Stitching is Subtractive

Whether you’re doing vertical, horizontal, or wack-a-doo stripes, remember that every time you add a line of stitching, you’re making the overall yardage skinnier and/or shorter. That’s because you’re either cutting off fabric or adding a tuck when you serge.

I *knew* this was happening as I worked on my serger stripes, but, TBH I was surprised how much shorter my yardage became. I probably lost 2-3 inches from the yard.

It’s a good thing to keep in mind. Maybe buy extra fabric, just in case.

Alright, over to you, my dear sewing doves: What do you make of “sergercore” and exposed seams? Yea or nay? How much have you used your serger for decorative applications (vs. seaming and finishing raw edges)? Please sound off in comments. Thanks for reading!